Intra-operative epicardial lesions in the atria using a multielectrode rf system

We examined radiofrequency (RF) ablation with a multiple coil electrode probe to create linear and transmural lesions from an epicardial approach. Finite element analyses (FEA) predicted that epicardial RF energy has to be applied continuously for longer than 3 min and at set temperatures higher than 80°C in order to overcome the convective cooling produced by the blood and to obtain transmural lesions. In vivo experimentation in six canines confirmed these predictions as transmural lesions were achieved only when the set temperature was increased to 80°C.